As an existing vehicle air-conditioning apparatus, there is a vehicle air-conditioning apparatus in which an indoor unit is provided on a roof of a railway vehicle, a pair of outdoor units are provided at both left and right end portions thereof, and further an inverter unit in which an inverter device is accommodated is provided between the indoor unit and one of the outdoor units. In the indoor unit, a fan motor is disposed, a pair of fans driven by the fan motor is disposed in front of and in rear of the fan motor, and a pair of indoor side heat exchangers are disposed at both outer sides of the pair of fans. During a cooling operation, cold air cooled by the pair of indoor side heat exchangers is blown into the inside of the vehicle by the fans, and part of the cold air is guided by a communication duct and discharged into the inverter unit to cool the inverter device (e.g., see Patent Literature 1).